From 4b9300bf83c2490ca9d2bfbd467bbdbc8809fc94 Mon Sep 17 00:00:00 2001
From: Peter Zijlstra <peterz@infradead.org>
Date: Mon, 3 Oct 2016 16:20:59 +0200
Subject: [PATCH] UPSTREAM: sched/core: Add missing update_rq_clock() in
 post_init_entity_util_avg()

Address this rq-clock update bug:

  WARNING: CPU: 0 PID: 0 at ../kernel/sched/sched.h:797 post_init_entity_util_avg()
  rq->clock_update_flags < RQCF_ACT_SKIP

  Call Trace:
    __warn()
    post_init_entity_util_avg()
    wake_up_new_task()
    _do_fork()
    kernel_thread()
    rest_init()
    start_kernel()

Change-Id: I0d8b0c83b19447dc53ebd397bb14f756cb97d8a3
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
(cherry picked from commit 4126bad6717336abe5d666440ae15555563ca53f)
Signed-off-by: Quentin Perret <quentin.perret@arm.com>
---
 kernel/sched/core.c | 1 +
 kernel/sched/fair.c | 1 +
 2 files changed, 2 insertions(+)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index fd10180d3072..dc4b5bd92916 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -2618,6 +2618,7 @@ void wake_up_new_task(struct task_struct *p)
 	__set_task_cpu(p, select_task_rq(p, task_cpu(p), SD_BALANCE_FORK, 0));
 #endif
 	rq = __task_rq_lock(p, &rf);
+	update_rq_clock(rq);
 	post_init_entity_util_avg(&p->se);
 
 	walt_mark_task_starting(p);
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index bd4bfdc7cd95..278378eaa3c9 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -10636,6 +10636,7 @@ void online_fair_sched_group(struct task_group *tg)
 		se = tg->se[i];
 
 		raw_spin_lock_irq(&rq->lock);
+		update_rq_clock(rq);
 		attach_entity_cfs_rq(se);
 		sync_throttle(tg, i);
 		raw_spin_unlock_irq(&rq->lock);